Your bug report

#23457: 24.5; interactive use of next-line and previous-line (holding down C-n or C-p) lag in a buffer with all spaces and newlines

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 23457@debbugs.gnu.org.

-- 
23457: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=23457
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